TEHRAN , Iran -LRB- CNN -RRB- -- Gunmen on motorcycles fired Friday on a campaign office for President Mahmoud Ahmadinejad , wounding two adults and a child , according to a report by Iran 's state-run news agency .

President Mahmoud Ahmadinejad was not present at the time of the attack .

The shooting happened about 5 p.m. in front of the entrance to the campaign office , campaign representative Mohammed Reza Zahed Shaikhi told IRNA .

Ahmadinejad , who is running for a second term in office , was not present . Iran 's presidential election will take place on June 12 .

The attack happened in Sistan-Balochistan province in southeastern Iran , the same province where a Shia mosque was bombed Thursday . Several suspects have been arrested in connection with Thursday 's attack in the town of Zahedan , which killed between 15 and 20 people , according to Iranian media reports .

No group publicly accepted responsibility for the mosque attack , but the provincial governor , Ali-Mohammad Azad , blamed a terrorist group that he said would be unveiled to the public once the suspects have been interrogated , IRNA reported .

Zahedan is about 1,100 km -LRB- 700 miles -RRB- southeast of Tehran , near Iran 's borders with Pakistan and Afghanistan .

Sistan-Balochistan province -- which shares a border with Pakistan -- is the site of frequent clashes involving Iranian police , drug dealers and armed groups . The province is located on a major narcotics-smuggling route between Afghanistan and Pakistan .

Azad said information on the arrested terrorist group would be unveiled to the public once interrogations were complete .

`` The terrorists and notorious gang planned to stir order and security in the province on the eve of -LRB- the June 12 presidential -RRB- elections , using ongoing insecurity in our eastern neighbors , '' he said Thursday .

Several days of mourning were reported to be under way for victims of the explosion .

Ayatollah Ahmad Khatami , a hard-line cleric who led Friday prayers in Tehran , said there were signs that the United States and Israel were involved in the mosque bombing , IRNA reported . The cleric , who put the death toll at 25 , condemned the bombing before a congregation on the Tehran University campus .

CNN 's Shirzad Bozorghmehr contributed to this report .

@highlight

Gunmen fire on campaign office for Iranian President Mahmoud Ahmadinejad ,

@highlight

Two adults and child wounded in attack ; Ahmadinejad not present

@highlight

Attack happened near where Shia mosque bombed Thursday , killing up to 20

@highlight

No group has accepted responsibility , but local governor blamed terrorist group